Fluid Mechanics

Pressure, flow and the machines that move fluids. How liquids and gases behave at rest and in motion. Learn fluid properties, hydrostatic pressure, continuity, Bernoulli's equation, momentum forces, laminar and turbulent flow, pipe losses, and the pumps, compressors and turbines that move fluids or extract energy from them.

• Fluid Properties — Fluids deform continuously under shear. Learn density, specific weight and gravity, viscosity (dynamic and kinematic), Newtonian vs non-Newtonian fluids, compressibility, surface tension, capillarity and vapour pressure.
• Pressure — Pressure is force per unit area in a fluid. Learn hydrostatic pressure p = ρgh, absolute vs gauge pressure, manometers, Pascal's law and hydraulic presses, forces on submerged surfaces and buoyancy.
• Continuity — Mass is conserved in a flow. Learn mass and volume flow rate, the continuity equation A₁V₁ = A₂V₂, flow in branching pipes, and compressible mass flow.
• Bernoulli Equation — Bernoulli's equation expresses energy conservation along a streamline: pressure, velocity and elevation heads trade off. Learn heads, Venturi and orifice meters, Pitot tubes, Torricelli's law and the extended energy equation with losses and pumps.
• Momentum — Moving fluid carries momentum; changing its speed or direction creates force. Learn the momentum equation for control volumes, jet forces on plates and vanes, pipe-bend reactions, thrust and water hammer basics.
• Laminar/Turbulent Flow — Flow is smooth (laminar) or chaotic (turbulent) depending on the Reynolds number. Learn Re, transition, velocity profiles, boundary layers and why turbulence matters for mixing, heat transfer and pressure loss.
• Pipe Flow — Friction and fittings cost pressure. Learn the Darcy–Weisbach equation, friction factor (laminar 64/Re, Colebrook, Moody chart), minor losses (K-values), system curves and how to size pipes and pumps together.
• Pumps — Pumps add energy to liquids. Learn centrifugal vs positive-displacement pumps, head, flow and hydraulic power, pump and system curves, efficiency, affinity laws, NPSH and cavitation, and series/parallel operation.
• Compressors — Compressors raise gas pressure. Learn reciprocating, screw, centrifugal and axial types, isentropic and polytropic work, efficiency, multi-staging with intercooling, free-air delivery and compressed-air system design.
• Turbines — Turbines extract energy from flowing fluids. Learn impulse vs reaction turbines, hydraulic turbines (Pelton, Francis, Kaplan), steam and gas turbines, power and efficiency, specific speed and turbine selection.